1. Field of the Invention
The present invention relates generally to cutting machines, and more particularly, to a cutter adapter for a cutting machine.
2. Description of the Related Art
A general cutting machine includes a drive shaft capable of reciprocating motion. A cutter adapter is mounted to a free end of the drive shaft for mounting a cutter thereto. When the drive shaft is moved, the cutter is driven to cut a workpiece.
Referring to FIGS. 1 and 2, a conventional cutter adapter is composed of a main body 1, two steel balls 2, a sleeve 3, and a spring 4. The main body 1 is column-shaped, having a first end 1a for connection with an output shaft of a cutting machine. The main body 1 includes a receiving tunnel 1c and two through holes 1d. The receiving tunnel 1c is provided with an opening formed at a second end 1b of the main body 1. The two through holes 1d are located at two lateral opposite sides of the receiving tunnel 1c. Each of the through holes 1d is provided with two openings formed at the sidewall of the receiving tunnel 1c and the external sidewall of the main body 1 respectively. The two steel balls 2 are located in the two through holes 1d respectively and each has two opposite parts exposed outside the two openings of one of the through holes 1d. The sleeve 3 is hollow and column-shaped, having an annular convex bevel 3a formed on its internal sidewall. The sleeve 3 is sleeved onto the main body 1 to enable the annular convex bevel 3a to face the exposed parts of the two steel balls 2. The spring 4 is mounted between the main body 1 and the sleeve 3 for pushing and keeping the sleeve 3 located at where the annular convex bevel 3a is stopped against the two steel balls 2.
In light of the above, push the sleeve 3 along its imaginary longitudinal axis to overcome the resilience of the spring 4 and to move to where the annular convex bevel 3a is away from the two steel balls 2, and then insert a tang of a cutter 6 into the receiving tunnel 1c of the main body 1. Next, release the sleeve 3 to enable the spring 3 to push the sleeve 3 to where the annular convex bevel 3a is stopped against the two steel balls 2 and to enable the two steel balls 2 to lie against the lock portion 6a of the cutter 6. In this way, the cutter 6 is locked to the cutter adapter. Reversely push the sleeve 3 along its imaginary longitudinal axis to overcome the resilience of the spring 4 for movement and then to enable the annular convex bevel 3a to disengage from the two steel balls 2. Accordingly, the cutter 6 can be freely removed from the cutter adapter.
While replacing the cutter from the conventional cutter adapter, the user's hand must keep pressing the sleeve 3 to keep the sleeve 3 located at where the annular convex bevel 3a is away from the two steel balls 2, such that the user's hand is subject to ache and uncomfortableness to cause the operational inconvenience. Besides, while replacing the cutter, the user not only keeps pressing the sleeve but also applies an axial stress to the drive shaft; if the drive shaft is not located at the top or bottom dead center of its moving path, removing the cutter will cause axial movement of the drive shaft to further potentially hurt the user.